Given an integer, write a function to determine if it is a power of three.
Example 1:
Input: 27 Output: true Example 2:
Input: 0 Output: false Example 3:
Input: 9 Output: true Example 4:
Input: 45 Output: false Follow up: Could you do it without using any loop / recursion?
- 一般这种情况都能通过枚举实现.1162261467是int的最大Math.pow(3,19);
class Solution {
public boolean isPowerOfThree(int n) {
return n > 0 && 1162261467%n == 0;
}
}